1. Field of the Invention
A needle specifically configured to enhance membrane penetration comprising a solid substantially cylindrical body having a penetration tip formed on the outer portion thereof.
2. Description of the Invention
It is usual practice in blood transfusions, intraveneous feeding or when fluids are to be withdrawn from the body to attach a tube to a hollow needle and insert the needle into a vein or other body cavity. The fluid then flows through the tube and hollow needle into or from the body.
Repeated punctures of veins with metal needles for withdrawing successive blood samples, delivering successive transfusions or intravenous feeding tend to cause venous thromboses and subcutaneous hematomas. To reduce such tramma, a common practice is to leave the needle in the body. Unfortunately, relative movement between the body and needle creates a continuing problem.
Thus, insertion of the soft flexible catheter into the body cavity or vein is desirable. This may be accomplished by inserting the end of the soft flexible catheter into the vein or body cavity by means of a needle and then withdrawing the needle. This is generally accomplished by using a relatively large hollow needle to form an incision, telescoping the soft flexible catheter through the hollow needle and then withdrawing the needle over the soft flexible catheter. Such a method of inserting a catheter tube produces a large incision and excessive cutting of the tissue. This is particularly undesirable when the incision is made in a vein. Such procedures are often painful and produce a coring effect.
Another such procedure may comprise the insertion of the catheter into the body cavity or vein by placing the catheter over a needle inserted into the body cavity or vein and then withdrawing the needle. This procedure or technique exhibits the same limitations and drawbacks as the technique previously described.
Thus, there is a need for an improved tissue piercing point, to reduce the penetration force required thereby minimizing the pain incident to the incision and substantially eliminating coring.
The following are examples of the prior art: U.S. Pat. No. 2,560,162; U.S. Pat. No. 2,716,983; U.S. Pat. No. 2,770,236; U.S. Pat. No. 2,282,744; U.S. Pat. No. 3,030,953; U.S. Pat. No. 3,067,742; U.S. Pat. No. 3,308,822; U.S. Pat. No. 3,477,423; U.S. Pat. No. 3,788,320; U.S. Pat. No. 3,893,445; U.S. Pat. No. 4,020,837 and French No. 1,225,009.